<?php

?>




<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>

.class{

}
</style>
</head>

<body>
    <div class="b">
        <br>
        <input type="text" placeholder="用户名">
        <br>
        <input type="text" placeholder="密码">
        <br>
        <input type="text" placeholder="年龄">
        <br>
        <button onclick="a()">登录</button>
        <br>
    </div>
</body>
</html>